[mutter] tests: Add test for unfullscreening followed by immediate strut change

[Marge Bot <marge-bot src gnome org>]

commit 989cc2e2476691361f9afa41dbd94a8a702b19c0
Author: Sebastian Keller <skeller gnome org>
Date:   Fri Oct 29 21:34:09 2021 +0200

    tests: Add test for unfullscreening followed by immediate strut change
    
    Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2066>

 src/tests/meson.build                              |  1 +
 .../stacking/unfullscreen-strut-change.metatest    | 49 ++++++++++++++++++++++
 2 files changed, 50 insertions(+)
---
diff --git a/src/tests/meson.build b/src/tests/meson.build
index 3d0aec394c..d084887be9 100644
--- a/src/tests/meson.build
+++ b/src/tests/meson.build
@@ -288,6 +288,7 @@ stacking_tests = [
   'restore-size',
   'unmaximize-new-size',
   'fullscreen-maximize',
+  'unfullscreen-strut-change',
   'restore-position',
   'default-size',
   'modals',
diff --git a/src/tests/stacking/unfullscreen-strut-change.metatest 
b/src/tests/stacking/unfullscreen-strut-change.metatest
new file mode 100644
index 0000000000..1a0005428c
--- /dev/null
+++ b/src/tests/stacking/unfullscreen-strut-change.metatest
@@ -0,0 +1,49 @@
+# Tests that the following works, both on Wayland and X11
+#  1. Create a window with a known size
+#  2. Fullscreen window results in fullscreen size
+#  3. Unfullscreen window followed by a strut change returns to known size
+
+new_client w wayland
+create w/1 csd
+
+resize w/1 500 400
+show w/1
+wait
+
+assert_size w/1 500 400
+
+fullscreen w/1
+wait_reconfigure
+assert_size w/1 MONITOR_WIDTH MONITOR_HEIGHT
+
+stop_after_next w
+unfullscreen w/1
+wait
+set_strut 0 0 1 1 top
+continue w
+wait_reconfigure
+assert_size w/1 500 400
+
+clear_struts
+wait
+
+new_client x x11
+create x/1 csd
+
+resize x/1 500 400
+show x/1
+wait
+
+assert_size x/1 500 400
+
+fullscreen x/1
+wait_reconfigure
+assert_size x/1 MONITOR_WIDTH MONITOR_HEIGHT
+
+stop_after_next x
+unfullscreen x/1
+wait
+set_strut 0 0 1 1 top
+continue x
+wait_reconfigure
+assert_size x/1 500 400